In recent years, the use of volatile organic compound (“VOC”) solvent systems has been discouraged due to their deleterious effect on the environment. Regulations have been promulgated not only in the United States but in countries throughout the world to accelerate the phase-out of environmentally destructive solvents. In addition to laws designed to prevent the use of these substances, product labeling requirements have also been promulgated to insure notice is given as to those compounds used as alternatives. Finding acceptable alternatives, however, has been an extremely difficult task. For example, in applications such as mold release compositions, the solvent must have low toxicity and a low VOC content, yet be sufficiently volatile to provide a good evaporation window for the resin cure time. In addition to these requirements, consideration must be given to cost factors, which are important for commercial feasibility.
In the U.S., the Environmental Protection Agency (“EPA”) promulgates rules and regulations regarding environmental concerns such as VOCs. EPA has defined a VOC to include any volatile compound of carbon which participates in atmospheric photochemical reactivity and which is not specifically exempted by the rules. See 40 C.F.R. § 51.100(s). Photochemical reactivity is the tendency to participate in reactions in the atmosphere that lead to ozone formation. This is ground-level ozone, also known as the main component in urban smog. Urban smog deleteriously impacts both human health and plant life, and thus, EPA increasingly regulates VOC emissions.
VOC emissions are produced by a number of various sources, one of which is the use of organic solvents classified as VOCs. As such, there is a need to reduce the use of conventional VOC solvents as carriers in solvent systems. It is apparent, therefore, that a need exists for a solvent system which has little or no VOC content yet has sufficient volatility for use as a carrier for active ingredients, such as moisture and/or heat curable components, as well as low in toxicity and affordable in cost.
The present invention overcomes problems associated with conventional VOC solvent systems for mold release compositions by employing non- or low-VOC solvents. Non-VOC solvents include certain of those removed from EPA's definition of a VOC because the compounds exhibit no or negligible photochemical reactivity. These compounds are exempt from EPA's definition of a VOC, and thus, are referred to as non-VOCs. In addition, non-VOCs may be combined with conventional VOC solvents to form low-VOC compositions. A typical mold release agent contains more than 90% by weight of inert organic carrier. Therefore, it is environmentally important to reduce or eliminate VOCs in release coating compositions.